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一、概况子午岭(古称圣人条)林区地跨陕甘两省,座落于黄土高原的中心地带,属乔山山脉支系,为泾河、洛河两水系之分水岭。东以洛河为界,西接马莲河,南起耀县,北至志丹县,面积约15,800平方公里。本区系大陆性气候。年降雨量一般为400—700毫米,多集中在7、8、9三个月。平均气温7—8℃,最高为36℃,最低为-29℃。无霜期120—160天。春秋多干风。植被属于森林草原型。据统计,全区约600余种植物,主要有山杨、小叶杨、白桦、辽东栎、油松、侧柏、虎榛子、酸刺、铁杆蒿、羽茅、白草、马牙草等。区内主要为黄土所
I. Overview Ziwuling (ancient sage article) across the Shaanxi and Gansu provinces forest region, is located in the heart of the Loess Plateau, is a mountain branch of Joe Hill, Jinghe, Luohe two watershed watershed. East of Luohe as the boundary, west of Malian River, Yao County from the south, north of Zhidan County, an area of about 15,800 square kilometers. The district of continental climate. Annual rainfall is generally 400-700 mm, mostly concentrated in 7,8,9 three months. The average temperature of 7-8 ℃, up to 36 ℃, the lowest -29 ℃. Frost-free period 120-160 days. Spring and autumn and more dry wind. Vegetation belongs to the forest grassland type. According to statistics, there are about 600 species of plants in the region, including aspen, Populus simonii, Betula platyphylla, Quercus liaotungensis, Pinus tabulaeformis, Platycladus orientalis, Tiger hazelnut, Acanthopanax senticosus, Artemisia ficus, Feathergrass, The main loess area